Revert "Add support for the new function-type syntax."

pkg/compiler/lib/src/js_backend/no_such_method_registry.dart

Index: pkg/compiler/lib/src/js_backend/no_such_method_registry.dart
diff --git a/pkg/compiler/lib/src/js_backend/no_such_method_registry.dart b/pkg/compiler/lib/src/js_backend/no_such_method_registry.dart
index ea0988801a0ce7419374745d05b2c2249ed04555..00b9ac7cda92327babbeae25613155c50fdab63b 100644
--- a/pkg/compiler/lib/src/js_backend/no_such_method_registry.dart
+++ b/pkg/compiler/lib/src/js_backend/no_such_method_registry.dart
@@ -219,8 +219,7 @@ class NoSuchMethodRegistry {
     }
     if (expr is Send && expr.isTypeCast) {
       Send sendExpr = expr;
-      var typeAnnotation = sendExpr.typeAnnotationFromIsCheckOrCast;
-      var typeName = typeAnnotation.asNominalTypeAnnotation()?.typeName;
+      var typeName = sendExpr.typeAnnotationFromIsCheckOrCast.typeName;
       if (typeName is Identifier && typeName.source == "dynamic") {
         expr = sendExpr.receiver;
       }